This invention relates to high-precision patterning and, more particularly, to an apparatus in which fine-line patterns are delineated by dry etching processes.
Considerable interest exists in employing dry processing techniques for patterning workpieces such as semiconductor wafers. The interest in dry processing techniques stems from their generally better resolution and improved dimensional and shape control capabilities relative to standard wet etching. Thus, dry etching is being utilized increasingly for, for example, pattern delineation in the processing of semiconductor wafers to form large-scale-integrated (LSI) devices.
Various dry etching processes that involve radio-frequency-generated plasmas are known. These processes include sputter etching which is described, for example, in J. Vac. Sci. Technol., Vol. 13, No. 5, pp. 1008-1022, Sept./Oct. 1976, and reactive sputter etching which is described, for example, in Proc. 6th Int'l. Vacuum Congr. 1974, Japan. J. Appl. Phys., suppl. 2, pt. 1, pp. 435-438, 1974.
Heretofore, so-called parallel-plate reactors have been utilized for sputter etching or reactive sputter etching of workpieces such as semiconductor wafers. In many cases of practical importance, however, it has been recognized that the throughput characteristics of available reactors have not been adequate for large-scale production of LSI devices. Accordingly, efforts have been directed at trying to devise high-throughput etching equipment that would be capable of simultaneously processing a relatively large number of workpieces. It was recognized that such equipment, if available, could substantially decrease the cost of devices processed therein.